b'Integumentary SystemChapterThis system consists of the skin, hair, fingernails and toenails.The skin:is the largest organ of the body. along with hair and nails, protects the body against infection by keeping disease-producinggerms out.is made of tough, elastic fibres that can stretch, thereby shielding against potential injury.keeps body fluids in, is waterproof and stops your body from drying out.protects you from the sun.helps make vitamin D and stores minerals.The Structure of the SkinThe outer surface of the skin (epidermis) is made of dead cells which are constantly rubbedaway and replaced by new cells.Oil glands contain a substance (keratin) to help keep the skin soft and waterproof.Sweat glands and pores help regulate body temperature.Blood supplies the skin with nutrients and helps provide the skin with its colour. A pigment called melanin controls how dark or light the skin is and how it reacts to sunlight.Nerves in the skin make it sensitive to sensations such as pain, touch and temperature. The pattern on your fingertips is different from anybody elses, your skin makes you completely unique.34 How Your Body Works'